A 22-year-old woman was admitted to the critical care unit in fulminant hepatic failure with acetaminophen toxicity related to an attempted suicide. She was comatose and her family relayed her medical...

A 22-year-old woman was admitted to the critical care unit in fulminant hepatic failure with acetaminophen toxicity related to an attempted suicide. She was comatose and her family relayed her medical history, which included a possible cause of the overdose. She had failed her senior year at the university and could not graduate with her friends. She had always been an average student so this was very disappointing to her parents and to her. She was listed urgently for a liver transplant as a status 1A. A new liver was transplanted within 36 hours. She did well for the first 2 days posttransplantation and was extubated within 12 hours. On post-op day 3 there was a sharp rise in her liver enzymes. A Doppler ultrasound revealed poor blood flow in the hepatic artery. Which laboratory tests are most indicative of hepatic artery thrombosis post–liver transplantation?